1. Field of the Invention
The present invention relates to an electric actuator capable of converting a rotating motion of a rotative driver to a linear motion for linearly reciprocating a moving member.
2. Description of the Related Art
Carrying means, such as an actuator, is used for carrying a workpiece.
FIGS. 12 and 13 show, by way of example, a prior art electric actuator disclosed in JP-A No. 11-30234.
Referring to FIGS. 12 and 13, an electric actuator 1 has a frame 2 provided with a guide groove 3, a slider 4 that moves in the guide groove 3, a nut 5 detachably attached to the slider 4 and a threaded rod 6 linked to the nut 5. Opposite end parts of the threaded rod 6 are supported on threaded rod support members 7a and 7b, respectively. The threaded rod support members 7a and 7b are placed on the upper surface 8 of the frame 2 and are fastened to the frame 2.
When the electric actuator 1 is operated, similarly to the hydraulic cylinder actuator, without using any complicated controller or the like to press the slider 4 against a workpiece disposed at an intermediate position between the opposite ends of the stroke of the slider 4, shock that acts on the slider 4 upon the contact of the slider 4 with the workpiece is transmitted to the threaded rod 6 and the associated parts, adversely affecting the durability of the electric actuator 1.